Electrode Lead

ABSTRACT

An electrode lead is provided having a distal side and a circumferential surface, the electrode lead comprising a plurality of interlocked filaments having a conductive core coated with a nonconductive coating and at least one 3D distinct conductive mass at the distal end, wherein the filaments in the conductive mass are having an exposed conductive core and wherein a portion of the filaments with the exposed conductive core are disposed on the circumferential surface. The 3d pattern of spaced-apart regions along or within the electrode lead, each one is a network of spaced-apart conductive segments determining together critical parameters of: directionality of the region and electrical property of the region.

FIELD OF THE INVENTION

The invention relates to electrode leads that can be used for sensing orstimulating electrical impulses in tissues and methods of producingsame.

BACKGROUND OF INVENTION

Electrical stimulation of bodily parts such as spinal cord, peripheralnerves, cranial nerves, nerve roots, muscles, or brain tissues is usedto treat various conditions including, for example, Parkinson's disease,dystonia, chronic pain, Huntington's disease, bradykinesia, epilepsy andseizures, eating disorders, and mood disorders. For those conditions aswell as others, sensing or recording electrodes are also available formonitoring the electrical activity of the tissues to be treated orstudied. Many of the electrodes, whether stimulating or sensingelectrodes, have similar characteristics.

Typically, an electrode for stimulation comprises a flexible, axiallyextending probe body with several annular or other structuralstimulation contacts distributed at equal or different distances along aregion of the probe body. Similar electrodes can be built for recordingphysiological potentials and neural activity in those tissues,especially brain tissues.

While optimizing stimulation of the electrodes based on therapeuticresults, a finer shaping of the electrical field formed by the electrodeis required, which in turn will shape an activating field (theactivation field is the actual area in the brain being affected byneuronal elements being activated and or inhibited by producedelectrical field). By directing the activation field towards desiredtissue region and limiting its extent from other regions, much betteroptimization can be performed, while increasing the therapeutic benefitto the patient and decreasing the side effects from the stimulation aspartially done with today's technologies only along the electrode leadand not in directions perpendicular to the lead axis. Optimizing theshape of the activation field requires, among other, to increase thenumber and resolution of the electrode contacts so as to increase theresolution of the activation field that can be accomplished. Therefore,the directionality of the electrode contacts is very important.

Currently marketed electrodes contain limited number of contacts; theseelectrodes are assembled manually or in a semi-automatic manner. Futureapproaches are directed towards other methods of electrode leadmanufacturing like Lithographic etching, electroforming, laser ablationand other to precisely manufacture electrode arrays with finer contactsand higher number of contacts. However, these methods are cumbersome andthe procedure is relatively long and as a rule, have limited andessentially two-dimensional surfaces, As the contact surface is smaller,the area contacting the body fluid or body tissue becomes smaller aswell and the electrical properties of the electrode are worsens (e.g.impedance of contact increases), resulting in potentially high currentdensities that might be harmful. It is extremely difficult to producearrays of small electrodes having complex shapes with a large number ofconductive surfaces, in particular asymmetric arrays that can be crucialin treating conditions as mentioned.

U.S. Pat. No. 5,330,524 discloses an implantable cardiac defibrillationelectrode, in which there is an electrically conductive wire mesh formedof crossed spirally wound cables. Each of the spirally wound cablesincludes a plurality of stranded wire elements, with a central wireelement and a plurality of outer wire elements wound adjacent to thecentral wire element. Such electrodes do provide flexibility and a largecontact surface area; however, the meshes described in U.S. Pat. No.5,330,524 are electrically conductive in their entirety, but are notsufficiently directional or area-specific for some applications.

Another example is described by Parker at al. in U.S. Pat. No.8,923,984. The disclosure depicts neurostimulator made of a knittedelectrode. In this case, there is a possibility to form contact areasthat are more specific since a conductive filament is intertwined withinnon-conductive filaments. Among other disadvantages of the disclosedstructure, the knitted electrode has relative large spacing betweenadjacent rows, a fact that prevents accurate and stable positioning ofthe electrode in a desired area that is usually very small.

The present invention, on the other hand, aims at addressing the needfor more specificity in controlling the size and positioning of the verysmall contacts on the electrode lead according to an aspect of theinvention as well as their critical properties their directionality andtheir electrical properties (e.g. impedance). The electrode leadaccording to the present invention is easily and accurately fabricated.

SUMMARY OF THE INVENTION

It is therefore provided in accordance with one aspect, an electrodelead having a distal side and a circumferential surface, the electrodelead comprising:

-   -   a plurality of interlocked filaments having a conductive core        coated with a nonconductive coating;    -   at least one 3D distinct conductive mass at the distal end,        wherein the filaments in the conductive mass are having an        exposed conductive core and wherein a portion of the filaments        with the exposed conductive core are disposed on the        circumferential surface.

It is therefore provided in accordance with one aspect, an electrodelead having a distal side and a circumferential surface, the electrodelead comprising:

-   -   3d pattern of spaced-apart regions along or within the electrode        lead, each one of said spaced-apart regions is a network of        spaced-apart conductive segments determining together critical        parameters of: directionality of the region and electrical        property of the region.

According to another embodiment, the conductive core of the filaments inthe conductive mass are extended to a proximal end of the electrode leadand are connected to an electronic module.

According to another embodiment, the interlocked filaments areinterlocked using one of the methods such as braiding, knitting,weaving, interwinding, entangling, or meshing.

According to another embodiment, said plurality of interlocked filamentsare arranged in layers.

According to another embodiment, said layers are axial.

According to another embodiment, electrical signals can be transferredthrough the conductive mass to or from the electronic module.

According to another embodiment, the electrode lead is provided with atleast one insert resides in between layers that comprise the electrodelead, and wherein filaments are passed through at least one slot in theinsert in an angle relative to an elongated axis of the electrode lead.

According to another embodiment, the filaments are cut at thecircumferential surface.

According to another embodiment, the insert can be positioned as aninner most layer.

According to another embodiment, the insert is extending only partiallyin the electrode lead.

According to another aspect, a method is provided of producing anelectrode lead comprising:

-   -   providing a machine capable of interlocking a plurality of        filaments into a 3D structure;    -   providing a plurality of filaments, a portion of the filaments        are nonconductive filaments and another portion of filaments        comprising a conductive core coated with a nonconductive        coating;    -   providing a laser capable of directing a laser beam towards the        filaments during interlocking;    -   interlocking said plurality of filaments according to a        premeditated program to form said 3D structure;    -   directing said laser beam to a one of said another portion of        filaments so as to expose said conductive core during said        interlocking said plurality of filaments.

According to another embodiment, said 3D structure is the electrode leadas described before.

According to another embodiment, the method further comprising providinga dispenser capable of directing material towards the filaments duringinterlocking and dispensing said material onto the plurality offilaments during said interlocking said plurality of filaments.

According to another embodiment, said machine is provided with a hollowcylinder onto which the 3D structure is interlocked.

According to another embodiment, the cylinder is provided with at leastone slot through which additional filaments can be transferred from thehollow to outside the 3D structure.

According to another embodiment, the method further comprising pullingthe additional filaments from the hollow through the slot in a directionopposite to the direction of said interlocking said plurality offilament.

According to another embodiment, the method further comprising cuttingthe additional filament adjacent to the circumferential surface.

According to another embodiment, wherein said machine is provided with aweaver having a rotating cylinder onto which the 3D structure isinterlocked.

According to another embodiment, said laser is incorporated within saidweaver.

According to another embodiment, the method further comprising providinga computing module and programming the computing module to instruct themachine according to a predetermined pattern of the 3D structure.

According to another embodiment, said programming the computing modulecomprises providing parameters from which characteristics of theelectrode lead are established.

According to another embodiment, said programming the computing modulecomprises providing characteristics of the electrode lead from whichparameters of said interlocking the plurality of filaments areestablished.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings. With specific reference now tothe drawings in detail, it is stressed that the particulars shown are byway of example and for purposes of illustrative discussion of thepreferred embodiments of the present invention only, and are presentedin the cause of providing what is believed to be the most useful andreadily understood description of the principles and conceptual aspectsof the invention, in this regard, no attempt is made to show structuraldetails of the invention in more detail than is necessary for afundamental understanding of the invention, the description taken withthe drawings making apparent to those skilled in the art how the severalforms of the invention may be embodied in practice.

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

While the disclosure is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be further described in detail herein below. Itshould be understood, however, that the intention is not to limit thedisclosure to the particular embodiments described. On the contrary, theintention is to cover all modifications, equivalents, and alternatives.

FIG. 1a illustrates a schematic drawing of distal portion of anelectrode lead according to an exemplary embodiment.

FIG. 1b illustrates a schematic cross sectional view of the electrodelead shown in FIG. 1 a.

FIG. 1c illustrates a schematic drawing of distal portion of anelectrode lead according to another exemplary embodiment.

FIG. 1d illustrates a schematic drawing of a cross section distalportion of an electrode lead along its axial axis.

FIG. 2a schematically illustrates a method of weaving layered lead inaccordance with exemplary embodiment.

FIG. 2b schematically illustrates method of weaving layered lead inaccordance with another exemplary embodiment.

FIG. 2c schematically illustrates method of weaving layered lead inaccordance with another exemplary embodiment.

FIG. 2d schematically illustrates method of weaving layered lead inaccordance with another exemplary embodiment.

FIG. 2e schematically illustrates method of weaving layered lead inaccordance with another exemplary embodiment.

FIG. 3 illustrates a method by which the gap between two adjacentfilaments is established in accordance with an exemplary embodiment.

FIG. 4 illustrates contact point on the surface of a lead made using themethod shown in FIG. 3 in accordance with an exemplary embodiment.

FIG. 5 illustrated a method by which action is inflicted on filamentsduring production process according to exemplary embodiment.

FIG. 6a schematically illustrates an apparatus for manufacture of aninterlocked structure according to exemplary embodiment.

FIG. 6b depicts a block diagram of a method of manufacturing anelectrode lead according to an exemplary embodiment.

FIG. 7a illustrates a portion of multilayered lead according to anexemplary embodiment.

FIG. 7b is an enlarged portion of the layers in FIG. 7 a.

FIG. 8 illustrates a cross sectional view of an electrode lead through acontact according to an exemplary embodiment.

FIG. 9a illustrates a cross sectional view of a distal end of anelectrode lead according to another exemplary embodiment.

FIG. 9b illustrates the cross sectional view of a distal end of theelectrode lead shown in FIG. 9a after expansion.

DETAILED DESCRIPTION OF THE INVENTION

According to aspects and embodiments of the present invention, a leadfor electrode and a method of producing the same are provided. Theembodiments are aimed at constructing a lead made of a plurality ofinterlocked filaments bundled to form a lead with electrode contacts inits distal side that may be also custom made. The interlocked filamentscan be manufactured by braiding, knitting, weaving, interwinding,entangling, meshing, or any other method by which the filaments areinterlocked into a specific predetermined structure. Any other method bywhich filaments can be interlocked into a three dimension structure thatcan act as an electrode is covered by the scope of the presentinvention.

The lead can comprise two types of filaments organized in layers—fullynonconductive filaments and filaments made of conductive material coatedby a nonconductive material. In order to form contact surfaces in thelead that are capable of transferring electrical signal in or out of thelead, a portion or a segment of the nonconductive coating is removedfrom the filament so as to expose the conductive material. A contactsurface is a surface made of several adjacent exposed areas in severalfilaments positioned in the outer layer of the lead.

The size of the surface can be predetermined in accordance with theactual area in the body that is to be stimulated through the electrodeso as to allow control of the flow of electric signals through thesurface. Each individual contact can be in a different size than theother and all in accordance with the specific needs and requirements ofthe specific individual and condition to be treated.

It should be emphasized that forming contacts using exposed conductiveportions of the filaments is a substantial advantage of the embodimentsthat will be disclosed herein after over prior art. The fact that thecontacts are part of the filaments renders the contacts positionalstability, e.g. the contacts cannot move relative the lead itself andcannot fall off; they are a part of the interlocked structure.

Another important feature of the disclosed lead is the directionality ofthe electrodes. Generally, the electrodes surface area is facing an axissubstantially perpendicular to the elongated axis of the lead. In thisway, there is full control of the area in the tissue to be stimulated ormonitored for electric activity. As an example, in treating Parkinsondisease, stimulating electrodes are positioned in deep brain tissues andare used to stimulate very specific tissues in a very specifictherapeutic time window. Nowadays, as an example, ring electrodes areprovided on a lead at several perimeters of the lead and the electricsignal is symmetrically transmitted about the lead. Therefore, theelectric field in not directed solely to the treated area, the flow ofelectrical signals all around the lead.

According to one aspect of the invention, since the size of the contactsurface is fully controllable and can be very small, more than onecontact can be provided on a certain perimeter about the lead. In thisway, the electric signal is fully directed to the area to be treatedwithout having signals that are directed towards unwanted areas.

Accordingly, reference is now made to the figures.

Reference is now made to FIG. 1a illustrating a schematic drawing ofdistal portion of a lead according to an exemplary embodiment. Distalportion 12 of a lead 10 is elongated and capable of reaching distal anddeep tissues or other targets in the body. Relatively small contacts 14are discretely distributed on the surface of the lead. The contacts 14allow electric signals to flow through its surface in order to stimulatethe adjacent tissue or in order to collect electrical signal, dependingon the requirements. In order to observe the inner structure, a crosssectional view in the A-A plane is shown.

Reference is now made to FIG. 1b illustrating a schematic crosssectional view of the lead shown in FIG. 1a . The lead 10 shown in thisfigure has an empty core 18 through which guide wires or similar medicaldevices can be inserted. As mentioned herein before, the lead is made ofinterlocked network of filaments. In this schematic figure, theindividual filaments are not shown. Interlocking possibilities toestablish a 3D structure of a lead will be shown herein after. Thefilaments are mainly made of conductive wire coated with an isolatingmaterial. The bulk of the lead comprises interlocked nonconductivefilaments. A portion of the nonconductive filaments can be filamentsthat are entirely nonconductive and a portion can be conductivefilaments coated with nonconductive material. In order to form theelectrode contact, the isolated nonconductive material is removed from aplurality of adjacent filaments (this issue will be elaborated hereinafter), to form a conductive mass 16 that acts as a 3D contact. Theplurality of exposed filaments in one area of conductive mass 16 areisolated from each other in order to prevent short circuits between thefilaments at the lead's distal end and to form one connector contact.The filaments are connected to each other at an electronic module in theproximal end of the lead so as to transfer the electrical signals fromthe contacts or collect the electrical information coming from thecontacts. The electronic module is not shown in the figures and anymodule available in the art or specific module can be utilized withoutlimiting the scope of the present invention.

The flow of electrical signals into and out from the conductive mass 16is possible through the outer surface area 14 of the contact that issubstantially aligned with the surface of the lead 10. Thedirectionality of the electric signals formed in the contact issubstantially determined by the outer surface area of the contact. Thelarger the conductive mass 16 is, the better the electrical propertiesof the contacts are (e.g. lower the impedance of the contact).Therefore, more current will flow through the surface area of thecontact. This feature is also important in sensing and recordingelectrode leads since this feature renders the electrode lead with lowersignal to noise ratio.

As mentioned herein before, the bulk of the lead is made of interlockedfilaments made of isolated conductive wires and the conductive mass areareas where the isolated coating of the wires is being removed.Therefore, a possibility opens for a vast variety of structures to beproduced.

Optionally and since the conductive masses are totally discrete and canbe made of very small surface area size, it is possible to use severalof the electrodes on the same lead as stimulating electrodes while otherelectrodes are being used as sensing electrodes. In this way, one cantreat the tissue and at the same time receive feedback from the same oradjacent tissue without the need to employ two separate surfaces forelectrode contacts on the same lead.

The filaments to be used for the electrode leads of the presentinvention are to be totally biocompatible with the body and made frommaterials that can be implanted within the body. As for the conductivecore of the filament, conductive metals can be used such as stainlesssteel, platinum, titanium, tungsten, iridium, cobalt alloys, orcombinations alloys. The isolation coating can be made of polymericmaterials such as Parylene, silicones, polyethylene, polyvinylchloride,polyurethanes, polylactides. Other materials can be employed withoutlimiting the scope of the present invention.

Reference is now made to FIGS. 1c and 1d illustrating a schematicdrawing of distal portion of an electrode lead and a cross sectionalview, respectively, according to other exemplary embodiments. Accordingto these examples, an electrode lead 20 has a plurality of 3D patternsof distinct and spaced apart regions 22 of conductive mass along thesurface (FIG. 1c ) and extend to within (FIG. 1d ) the electrode lead20. These patterns can be of various surface area shapes, while animportant aspect is the directionality of the surfaces that can bepredetermined and is directly linked to the lead circumference span ofthe contact. Generally, as the span is lower and the surface area of thecontact is smaller, the electrical properties of the contact are worsen(e.g. higher impedance); it is desired that the electrical properties ofthe contact will be within certain limits so as to compensate for thisdegradation and produce a contact that have appropriate electricalproperties. According to one of the aspects of the present invention,the contact structure is made of a volume that contains conductivenetwork of exposed segments of plurality of filaments so that the totalsurface area of the conductive elements that is in contact with the bodytissue or body fluids is substantially equal to a surface area of aplanar contact adapted to yield the same electrical property. Forexample, a highly used deep brain stimulation (DBS) electrode having acylindrical contact with a length of 1.5 mm and a diameter of 1.27 mmyields an impedance (tested in laboratory) of around 500 Ohm, which isdirectly related to contact surface area which can be calculated as6.123 mm̂2 (external surface area of the contact). In order to produce adirectional contact with a quarter external surface area and the sameimpedance, it is required that the total surface area of the contactmass altogether be equal to 6.123 mm̂2. This is accomplished by producinga volumetric contact (conductive mass) with spread apart conductivefilaments defining the required surface area.

Reference is now made to FIG. 2a-2e schematically illustrating severalpossible methods of weaving layered lead in accordance with exemplaryembodiments. In order to form a lead, weaving of filaments in layers ispreferably used. As mentioned herein before, weaving is one of themethods of interlocking the structure of the lead in accordance withembodiments disclosed herein. The filaments to be used can be ofdiameters as small as 8 μmeter; therefore, a lead can be produced withlayers having width of about once or twice the diameter of thefilaments. Using the method disclose herein, leads of relatively smalldiameter can be produced. As a comparison, using one of the newtechnologies, 3D printing, one can think of the possibility of buildinga lead of electrodes having a diameter in the range of 100 μmeter. Usingthe weaving technology may produce leads of much lower diameters thatcan be used for different application in a much accurate manner that canbe established with today's leads.

A first simplified axial pattern is shown in FIG. 2a . Horizontalfilaments 102 are running from left to right to establish a layerarranged about an elongated axis. Weaving filament 107 weaves thehorizontal filaments 102 together in a weaving pattern that is fairlyknown in the weaving art. The width of the layer is twice the diameterof a filament in its maximum.

FIG. 2b illustrates another weaving axial pattern where the weavingfilament 107 surpasses each time over two horizontal filaments 202 andone filament when passes bellow the horizontal filaments; and so forth.This pattern can be woven on the opposite side of the layer. The weavingfilament 107 can surpass bellow two horizontal filaments 102 andimmediately after pass above one horizontal filament 102. Anycombination of these patterns can be accomplished. Also here, the widthof the layer is twice the diameter of a filament in its maximum.

FIG. 2c illustrates a method by which another pattern can be achieved intwo layers: a first layer with the simplistic woven structure shown inFIG. 2a is formed e.g. horizontal filaments 102 woven together byweaving filament 107, and another layer can be formed in the samemanner; however, in the pattern shown in FIG. 2c , the two layers areinterlocked together in occasional exchanging points 204. It can be seenthat this pattern does not necessarily form an axial structure, butrather, a flat structure.

FIG. 2d shows another example of weaving profile that is axial.Horizontal filaments do not assume a horizontal path, instead theyextend in a helical pattern 102 about an elongated central axis. Weavingfilament 107 assumes a helical opposite pattern that interlocks with thehelical pattern 102 of the horizontal filament. This woven structure canhave stretching capability along the elongated central axis of the leadas well as more flexibility.

In FIG. 2e , a structure is shown that is based and combines thestructures shown in FIGS. 2b and 2c . The horizontal filaments 102establishes more than two layers, in this particular case, three layers,each can assume a certain pattern using the weaving filament 107. Alllayers can be interlocked while even distant layers can have exchangingpoints 207 as well as exchanging points 205 between adjacent layers. Inthe example shown in this Figure, if we follow a certain filament fromthe middle layer—filament 206—it can be seen that in exchanging point205, which interlocks the upper layer and the middle layer, filament 206will exchange layers from the middle layer to the upper one. Followingfurther filament 206 to the right, the filament 206 is exchanging layersfrom the upper layer to the bottom layer in exchanging points 207.

Such exchanging points between the layers in the structure can form alead having integrated layers that result in a 3D structure that isstronger and can endure high inflicted pressures. According to oneaspect of the present invention, conductive masses are presented in thedistal portion of the lead and occupies portions in the volume of theconductive mass as well as the surface area on the outer circumferenceof the lead. In case exchanging points are to be used, one should makesure when designing the layers, that each filament can have one exposedarea with conductive characteristic, no matter if the filament istravelling among the layers from the surface are to the volume of viceversa.

Many other patterns can be produced using the methods depicted in thisdisclosure. It should be understood that any pattern that can beproduced according to the methods described herein and other methodsknown in the art are covered by the scope of the present invention andby no means, the patterns shown herein limits the scope of the presentinvention.

It should be mentioned that all those patterns as well as other patternsare formed on a supporting frame or using supporting elements that arenot shown in these figures and at least some will be shown in exemplaryembodiments herein after.

One of the advantages of the method by which the 3D structures are builtfrom the filaments as disclosed herein is the possibility to determineand control the gaps between the woven filaments. The gaps between thefilaments can be equal all through the lead and can be different indifferent areas of the lead. As an example, the gaps between filamentscan be larger in the proximal portion of the lead and smaller in thedistal portion, where the conductive masses are formed. The gaps betweenthe filaments render strength and stability to the lead as well as tothe conductive masses having a surface area on the perimeter of thelead. Moreover, the gaps between the filaments increase the flow ofelectrical signals in and out from the conductive mass and basicallyassist in increasing the effective surface area of the contact withoutdecreasing its directionality

In order to form a stable and strong enough 3D structure, the gapsbetween the filaments should be controllable. In accordance with themethod of the present invention, total control of the manufacturingprocess is achieved as will be explained herein after.

Reference is now made to FIG. 3 illustrating a method by which the gapbetween two adjacent filaments is established in accordance with anexemplary embodiment. It was already mentioned that supporting frames orstructures are facilitating the methods by which a 3D structure isbuilt. Supporting hollow cylinder 300 is provided with a slotted opening302 that passes through the elongated axis of the cylinder connectingthe hollow of the cylinder and its outer part. The supporting cylinderis an insert 300 that is assisting in establishing an axial built up ofa pattern similarly as disclosed herein in FIGS. 2a and 2b . The layersare built on the cylinder 300, each after the other, as needed using thefilaments. In this case, the gaps between the weaving filament 304 areconsidered. Along the longitudinal axis of the cylinder, a slot 302 ismaintained, wherein the slot is made to be very thin so as to allow afilament to pass through it. Within the hollow in the cylinder, a groupof filaments 306 is extending through both ends of the cylinder. Thelength of the insert can vary.

During weaving of the weaving filament 304, one or more filaments 308accommodated within the hollow are being pulled through the slot and inopposite direction to the advancement of the weaving filament. Aftereach winding of the weaving filament 304 or after several windings, afilament 308 is pulled from within the hollow and compresses the weavingfilament backwards and towards the preceding winding of the filament.Using this embodiment, the windings of the weaving filaments are fullycompressed one onto the other with a gap that can be determined by theintensity of the pulling or compressing action of the filament 308.

Optionally, pins or other elements can be positioned in a predeterminedmanner on the outer surface of the cylinder in order to formpredetermined gaps between adjacent filaments.

Optionally, slotted structure can include plurality of slots, or slotsthat does not necessarily run parallel to the lead axis, the purpose ofthese slots is to determine the location on the lead circumference wherethe weaved internal filament protrude. In addition, interlocking thefilaments together will yield a final cross section that suits the crosssection of the slotted structure, one of the reasons being that all theinternal filaments are contained within the slotted structure andprotrude only when they turn during the weaving.

The ability to control the gaps between the filaments can assist incases, as an example, in which a 2D structure is being built up. Thereare many cases in which a lead of electrodes should correspond to acertain bodily part in a human, such as in retinal prosthesis, as anexample. Although the retina is a 2D structure as well, it forms a 3Dstructure due to its curvature characteristic. In order to form such 3Dstructure, a 2D structure such as the one shown in FIG. 2c is built withgaps that then can assist in curving the structure to a 3D structure.

It should be added that curving the flat structure can be performed inother ways without limiting the scope of the invention. In another way,the layer can be weaved flat, after which it can go through certainprocessing that can deform the layer into its three dimensional finalstructure.

Optionally, another way is to weave the flat lead from multiple layersthat are being deformed by heat. The lead is being heated using heatimages such as holographic laser or holographic IR mages that areprojected on the lead. The lead then assumes a final shape from theimage according to a desired final form. This also can be done in aniterative manner where a heating image could be projected on the leadmade of weaved layers that causes a slight deforming. Then, anotherimage can be projected to cause another slight deformation. Thisprocesses is repeated until the final desired shape is assumed. Othermethods of deformation are possible.

Going back to FIG. 3, it is also possible to form contact surfaces usingfilaments 308 that are left protruding from the structure of the leadafter winding the weaving filament 304. In this case, the filaments thatare used as compressing filaments 308 has to be made of conducting wirecoated with an isolating material. Cutting the filaments form contactpoints on the surface of the lead.

Reference is now made to FIG. 4 illustrating contact points on thesurface of a lead made using the method shown in FIG. 3 in accordancewith an exemplary embodiment. Lead 400 is produced using the methodexplained in connection to FIG. 3. From convenience reasons, only theweaving filament 402 is shown and only one layer is presented. Thehorizontal filaments are not seen. Relatively constant distance gaps 404are provided between the windings of the weaving filament 402. Asexplained, the compressing filaments that according to some features ofthe method are protruding from the surface are cut so that their innerconductive cross section 406 is exposed on the surface of the lead 400.Those contacts can be as small as the diameter of the conductive core ofthe filament or of several such cores.

According to the method of the present invention, the contact massesthat form the electrodes in a lead are made by removal of thenonconductive coating of the filament and exposing the conductivematerial. One of the methods of doing so is to ablate the nonconductivematerial of the filament using a laser beam. This method can ne employedfor various other actions that should be inflicted onto the filament.

Reference is now made to FIG. 5 illustrating a method by which action isinflicted on filaments during the building process according toexemplary embodiment. Actions that can be inflicted onto the filamentsduring processing are actions such as filament cutting, gluing, welding,ablating, materials depositions or injecting isolation materials such asgels, glues or polymers examples for the purpose of controllingconductivity. The method as shown in FIG. 2a is employed and horizontalfilaments 102 are interlocked with weaving filament 107. This isperformed on a support rod 500. As an example, a laser head 601 isprovided and connected onto a machine such as a weaver (not shown inthis figure). Laser head 601 is sending a laser beam 602 according to apremeditated program so as to ablate the nonconductive material of theconductive wire or the energy suffice for cutting the filament so as toexpose its conductive core. In the same manner, glue, insulating gel orother materials dispenser injection needle can be provided to themachine, wherein the dispenser is capable of injecting required amountsof glue to adhere the filaments or insulting gel to form an insulationarea within the lead. Similarly, welding can be inflicted onto thefilaments. In cases where glue or insulating material is dispensed ontothe structure, an additional laser beam or lighting can be provided tothe production machine so as to activate and cure the glue over thefilaments in precise places.

Due to the extreme accuracy of ablation of the nonconductive materialoff the conductive core of the filaments during processing and asmentioned before, relatively small electrodes can be produced and inspecific needed areas of the lead that correspond the need of treatment.As indicated herein before, in the example of the Parkinson disease, itis extremely important to be able to direct the electrical signals tovery specific areas in the patient's brain tissue. As the electrodeproduced according to the method disclosed is very small and can befabricated in any area of the lead, it can be custom made in a size andlocation that is specific to the treatment of a specific patient. Thesefeatures renders the ability to place more than 1-2 contacts so as tosignificantly increase the resolution of the treatment. This feature isnot presented by any of the electrodes that are being used in the art ordisclosed.

According to another aspect of the invention, a system is provided thatis configured to allow manufacture of the interlocked structure.

Reference is now made to FIG. 6a schematically illustrating an apparatusfor manufacture of an interlocked structure according to exemplaryembodiment. The apparatus 600 comprises a command module 602 that isprogrammed with at least one weaving program, and a weaver 604 that isoperationally coupled to the command module 602. The command module 602controls the operation of the weaver 604 as well as the program by whichit weaves the 3D structure. The command module 602 can be connected orintegrated with a computing apparatus or module that can be providedwith a plurality of programs to produce electrode leads of common use,there may be also a default program. The command module 602 orintegrated computing apparatus can also be provided with a predeterminedprogram that is built for a specific use and for a specific patient.Each patient may have different physical characteristics and therefore,producing specific lead for a specific patient can enhance the treatmentin a significant manner.

The command module receives instructions from dedicated software thatdetermine characteristics of the structure to be built. Thecharacteristics to be determined are characteristics such as: thepattern or patterns to be used, type of filaments, number of layers,interlocks between the layers, the amount and size of contacts, the gapbetween the filaments, which filaments are to be used, isolation addedto the contact, scan of a specific patient from which certain parametersshould be extracted, application of isolating material, type ofelectrodes, etc. In accordance with the method of manufacturing the leadof the present invention, it should be emphasized that the process is tobe fully computerized so that industrial electrode leads as well ascustom-made electrode leads can be easily designed and manufacturesusing the dedicated software that instruct the manufacturing machine.

The weaver 604 has a cylindrical core 606 upon which the filament 608 iswound. A bobbin 610 provides the filament that is engaged with thecylindrical core 606 that rotates to receive the filament. Horizontalfilaments are placed in their positioning using several arms 614 thatare arranged on both sides of the cylindrical core 606, substantiallyparallel to the core, and around it. In order to simplify the figure,only few arms and even fewer horizontal filaments are shown, however,the number of arms around the cylindrical core can be very high and thenumber of arms that will be engaged in the production of a certainelectrode lead is dependent on the amount of horizontal filaments thatis needed for a certain lead. Each arm has an opposite arm on the otherside of the cylindrical core 606. The arms 614 are extendable and eacharm can hold an end of one horizontal filaments at its free end. Themovement of the arms is controlled by the program in the command module602 that determines if a certain horizontal filament that is engagedwith the right arm, as an example, will be covered by the weavingfilament 608 as the cylindrical core 606 rotates, whereas filamentengaged with the left arm will not be covered and will be placed abovethe weaving filament. Thus, an interlocked structure of the filaments isformed. The possibilities of the patterns is vast and is fed to theprogram in the command module 602.

As indicated herein before, the filaments are nonconductive, however, asubstantial number of the filaments are made of a conductive core orwire with an isolating coating. In order to form the electrodes andtheir contact surfaces, a portion of the nonconductive coating is to beremoved. For this purpose, the weaver 604 preferably comprises a highpower laser 616 that is capable of ablating the nonconductive coatingfrom the filament so as to expose the conductive material that can actas an electrode. Again, the areas in which the nonconductive coating isremoved are predetermined according to the active program fed to thecommand module 602. Preferably, the laser 616 is affixed to thecylindrical core 606, or at least rotates relative to the arms 614. Inthis way, as the cylindrical core 606 rotates, various filaments aroundthe circumference of the cylindrical core can be exposed to a laser beam618 from the laser 616.

Optionally, more than one laser is provided to the apparatus 600 thatmay be synchronized with the other laser or may be independent or workas a backup.

Optionally, when one of the arms 614 holds a horizontal filament 612that is programmed to be exposed to a laser beam, they are positioned atthe time of the exposure close to its placement on the cylindrical core606. Thus, the filament in this position is essentially perpendicular tothe cylindrical core and is the only filament that is positioned in thepath of the laser beam. In this way, there is minimal exposure if any,of other filaments to the beam and the exposed area on the filament isof minimal and accurate size and consistently defined.

It is noted that in FIG. 6, the laser 616 is positioned on the righthand side of the cylindrical core 606 and therefore, the filaments arebeing exposed on the side of the filament that face the cylindrical core606. The exposed or conductive area of the filament will be in this caseon the internal side of the layer that is being built. In someembodiments, the laser can be positioned on the left hand side of thecore and in this way, the exposures are on the exterior side of theformed layer. Optionally, there are lasers on both sides of the core,allowing contacts to be formed on both the interior and the exteriorside of the interlocked structure.

Optionally, a dispenser similar to the one disclosed and described inregard to FIG. 5 can be added to the apparatus 100 so that during theprocessing of the electrode lead, glue or isolating materials can beplaced on the filaments or woven structures.

Optionally, other means can be used to remove the isolated coating andexpose the conductive materials from inside. Any other means is coveredby the scope of the present invention and by no means limits theinvention.

After one layer is being formed on the cylindrical core, it is optionalto form another layer on top of it. For this purpose, the interlockedlayer may be left in the weaver 604 and another layer may be woven ontop of it, to make a multilayer interlocked lead. Several layers may beformed one of top of the other in this way. The top layer or theinterior layer may be left unexposed on the interior or exterior side tohelp isolate the lead from tissue that should not be stimulated orsensed (according to the tissue and application).

Upon completion of the weaving process, the interlocked structure thatcomprises the lead with conductive mass having contacts on the lead'ssurface is removed from the apparatus 600, and connected to a suitableelectrical circuit so that the conductive mass can be used as electrodesthrough which electrical signals are transferred.

Reference is now made to FIG. 6b depicting a block diagram of a methodof manufacturing an electrode lead according to an exemplary embodiment.As mentioned herein before, in accordance to one of the aspects of thepresent invention, a production machine 650 is producing an interlockedstructure made of filaments. The production machine 650 can be a weavingmachine, a sewing machine, braiding machine, or any other machine thatis capable of interlocking filaments into a structure that ispredetermined. In order to predetermine the structure of the electrodelead to be produced in the machine, a computing module 652 is providedthat can calculate information received from several sources andtransfer the results to a command module 658 that, in turn, activate themachine 650 to produce the resulting product according to the commands.The command module 658 can instruct the machine to operate in a certainmanner, to move elements from place to place according to a certainprogram so as to interlock the filaments in a predetermined manner. Inaddition, the command module 658 also provide instructions to the lasercommand 664 so as to ablate the filaments and expose the conductivematerial in a predetermined area of the filament that will be placedexactly in a place that can be in the conductive mass (surface orvolume). In a similar manner, should materials be disposed inpredetermined areas of the 3D formed structure, instructions from thecommand module will be delivered for this feature as well 662.

Optionally, some of the units can work together or being integrated towithin one single unit or module.

The program that is calculated in the computing module 652 receivesinformation from at least two sources: information coming from known andpredetermined structure programs known in the industry 654. Anothersource is the custom-made source 656 from which the calculating module652 should produce a custom-made electrode lead. Examples of theinformation needed here can be information on the resolution needed forthe electrode, the size of the surface of the contact directional to thetissue and the whole surface of the exposed areas, contact masselectrical properties needed, flexibility of the lead etc.

Reference is now made to FIGS. 7a and 7b illustrating in details aportion of multilayered lead according to an exemplary embodiment. FIG.7a illustrates a portion of a lead made using an apparatus such as theone disclosed in FIG. 6. The portion of the lead 700 comprises 3 layers,702 a, 702 b, and 702 c, wherein 702 a is the outermost layer of thelead. The layers shown in the Figure are very simplistic so as to beable to understand the structure. In FIG. 7b , the structure of thefilaments in the layer is better seen. Plurality of horizontal filaments704 are interlocked with weaving filaments 706. As explained before, aportion of the horizontal filament is being ablated before it is beinginterlocked into the structure. As a result, a portion of the horizontalfilament 704 is a conductive wire 708. In this specific case, one cansee that all layers are of the same organization of filaments and theportion that is exposed, conductive wire 708, is of the length ofsubstantially four times the filament's diameter since this portionsurpasses 4 adjacent weaving filaments 706.

The conductive wire 708 shown in FIG. 7b that is positioned on the mostouter layer 702 a correspond to the surface area of contacts 14 shown inFIG. 1b and the conductive wires in the layers beneath it correspond theconductive mass 16 shown in the same FIG. 1 b.

It should be noted that the interlocked structures formed using themethod described herein are flexible. This renders the ability of thedistal portion of the electrode lead to conform to the target area in abetter way than existing electrodes. The interlocked structure made offilaments in accordance with the embodiments of the present inventionalso has longer fatigue life because for similar deflections and motionsthe electrode lead is inflicted with. The stress levels for the smallerstructure is greatly lessened. In addition, each filament is redundantallowing for continuing functionality even if it breaks. The interlockedstructure allows for a larger amount of electrode surface area to beexposed to the target area, thus lowering current densities at theelectrode/tissue interface.

As mentioned herein in regard to FIG. 5, a dispenser can be added to theapparatus to add adequate materials during the manufacturing process.

Reference is now made to FIG. 8 illustrating a cross sectional view ofan electrode lead through a contact according to an exemplaryembodiment. An electrode lead 800. A conductive mass 804 made of aplurality of interlocked and exposed filaments is provided. Thecircumference of conductive mass 804 is provided with a plurality ofisolation spots 806 that can be provided also on the circumference ofthe electrode lead 800 itself. This feature of providing isolation spotsis possible due to the method in which the the structure is manufacturedusing a machine that interlocks the filaments while during theprocessing of the filaments, materials can be added to the structure aswell as actions inflicted on them. Due to the fact that the procedure isfully computerized, the exact filament or structure onto which thematerial should be dispensed is located and therefore, the positioningof such isolation spots is accurate.

The need of the isolation spots arises from the structure of theelectrode lead that comprises interlocked filaments. As alreadyindicated, interlocked filaments that comprises the conductive mass arehaving their conductive parts exposed. When the electrode lead is in thebody, the liquids of the body are entering the structure and may causethe electrical signals to pass internally within the lead. Placingisolated spots between the contacts and the nonconductive areas preventsthis phenomena.

Another use of such spots can be to form conductive paths between twodistinct contacts. This may be desirable when a return current isneeded. For example, in cases where some of the lead contacts areconnected to different current sources at the lead proximal end, if theproduced total current is not equal to zero, one of the lead contactscan internally be connected to a return electrical ground that act as asink for all the extra current.

Reference is now made to FIGS. 9a and 9b illustrating a cross sectionalview of distal end of an electrode lead according to another exemplaryembodiment. The distal end of the lead 900 is enclosing a stent 902 thatis capable of expanding. Conductive mass 901 are provided also at thedistal end. Such electrode lead can be beneficial during leadimplantation since during implantation, the lead diameter should besmall in order to be easily and safely inserted while after implantationto the correct target place, the distal end of lead can expand in itsdiameter, as an example, and can be enlarged as and when required. Indeep brain stimulation electrode, as an example, it can be desired thatthe lead diameter during implantation be less than 0.8 mm and afterimplantation to be about 1.3 mm. In this example, the network ofinterlocked structure filaments of the lead is formed to be stretchablealong the lead's elongated axis and enlarged in diameter as described inearlier embodiments of the present invention. This exemplary electrodelead allows the implantation of the lead when it is in its minimaldiameter at the distal end, while once the lead is implanted, the distalend will be increased by forcing the stent to gain its longer diameteras shown in FIG. 9b . It can also be seen that the surface area of thelead increases when the distal end diameter is increased. It is alsopossible to keep the total surface area of the contact unchanged duringenlargement.

It should be noted that other mechanisms of expansion such as a ballooncan be used to enlarge the electrode lead diameter without limiting thescope of the present invention.

It should be noted that since the electrode leads of the presentinvention are to be implanted in the body, the materials from which theyare comprised should accord the MR conditionals and withstand MRIenvironment. Moreover, since the electrode lead of the present inventionis made of interlocked filaments passing along the lead's axis whileother configuration running in different directions then it will bepossible to create filaments configurations that are electromagniticallycompatible, this is accomplished by for example creating filaments withconductive cores running in special loops in opposite directions thateliminate interference with electromagnetic fields such as MR at thesame time reducing radiated transmission from the lead.

Optionally, regular ring or other electrodes can be combined within thestructure of the electrode lead according to the present inventionwithout limiting the scope of the invention.

Optionally, if sensing and stimulating electrodes are to be usedtogether, it is possible to combine the two in a single conductivemass—several filaments will be used for the sensing electrodes and theother filaments will be used for the stimulating electrodes.

It should be emphasized that although weaving of filaments was chosen tobe an exemplary embodiment for interlocking filaments in thisdisclosure, it should be understood that other interlocking methods arein the scope of the present invention and by no means limits the scopeof the invention.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the variousembodiments of the invention without departing from their scope. Whilethe dimensions and types of materials described herein are intended todefine the parameters of the various embodiments of the invention, theembodiments are by no means limiting and are exemplary embodiments. Manyother embodiments will be apparent to those of skill in the art uponreviewing the above description.

This written description uses examples to disclose the variousembodiments of the invention, and also to enable any person skilled inthe art to practice the various embodiments of the invention, includingmaking and using any devices or systems and performing any incorporatedmethods. The patentable scope of the various embodiments of theinvention is defined by the claims, and may include other examples thatoccur to those skilled in the art. Such other examples are intended tobe within the scope of the claims if the examples have structuralelements that do not differ from the literal language of the claims, orif the examples include equivalent structural elements withinsubstantial differences from the literal languages of the claims.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims. In addition, citation or identification of anyreference in this application shall not be construed as an admissionthat such reference is available as prior art to the present invention.

The scope of the present invention is defined by the appended claims andincludes both combinations and sub combinations of the various featuresdescribed hereinabove as well as variations and modifications thereof,which would occur to persons skilled in the art upon reading theforegoing description.

1. An electrode lead having a distal side with a circumferential surface, and a proximal side, the electrode lead comprising: a) a plurality of interlocked filaments having a conductive core coated with a nonconductive coating; and b) at least one 3D distinct conductive mass at the distal side, extending to a 3D conductive mass at the proximal side of the electrode lead constituting an electrode lead mating connector for connection of an electronic module, such that electrical signals can be transferred between said at least one 3D distinct conductive mass and said electronic module, wherein the filaments in said 3D conductive mass have an exposed conductive core and wherein a portion of the filaments with the exposed conductive core are disposed on the circumferential surface.
 2. The electrode lead of claim 1, comprising: 3d pattern of spaced-apart regions along or within the electrode lead, each one of said spaced-apart regions is a network of spaced-apart conductive segments determining together critical parameters of: directionality of the region and electrical property of the region.
 3. (canceled)
 4. The electrode lead as claimed in claim 1, wherein the interlocked filaments are interlocked using one of the following methods: braiding, knitting, weaving, interwinding, entangling, or meshing.
 5. The electrode lead as claimed in claim 1, wherein said plurality of interlocked filaments are arranged in layers, wherein said layers are optionally axial. 6-7. (canceled)
 8. The electrode lead as claimed in claim 1, wherein the electrode lead is provided with at least one insert resides in between layers that comprise the electrode lead, and wherein filaments are passed through at least one slot in the insert in an angle relative to an elongated axis of the electrode lead, wherein the filaments are optionally cut at the circumferential surface.
 9. (canceled)
 10. The electrode lead as claimed in claim 1, wherein the insert is positioned as an inner most layer, or is extending only partially in the electrode lead.
 11. (canceled)
 12. A method of producing an electrode lead comprising: a) providing a machine capable of interlocking a plurality of filaments into a 3D structure; b) providing a plurality of filaments, some are nonconductive and others comprising a conductive core coated with a nonconductive coating; c) providing a laser capable of directing a laser beam towards the filaments during interlocking; d) interlocking said plurality of filaments according to a premeditated program to form said 3D structure; and e) directing said laser beam to a one of said another portion of filaments so as to expose said conductive core during the interlocking of said plurality of filaments.
 13. The method as claimed in claim 12, wherein said 3D structure is the electrode lead of claim
 1. 14. The method as claimed in claim 12, further comprising providing a dispenser capable of directing material towards the filaments during interlocking and dispensing said material onto the plurality of filaments during the interlocking of said plurality of filaments.
 15. The method as claimed in claim 12, wherein said machine is provided with a hollow cylinder onto which the 3D structure is interlocked, wherein said cylinder is optionally provided with at least one slot through which additional filaments can be transferred from the hollow cylinder to outside the 3D structure.
 16. (canceled)
 17. The method as claimed in claim 12, further comprising, a step of pulling the additional filaments from the hollow cylinder through the slot in a direction opposite to the direction of the interlocking of said plurality of filament, and optionally cutting the additional filament adjacent to the circumferential surface.
 18. (canceled)
 19. The method as claimed in claim 12, wherein, said machine is provided with a weaver having a rotating cylinder onto which the 3D structure is interlocked, and optionally said laser is incorporated within said weaver.
 20. (canceled)
 21. The method as claimed in claim 12, further comprising the step of providing a computing module and programming the computing module to instruct the machine according to a predetermined pattern of the 3D structure, wherein said programming the computing module comprises: providing parameters from which characteristics of the electrode lead are established, or providing characteristics of the electrode lead from which parameters of said interlocking the plurality of filaments are established. 22-23. (canceled) 